VMS vs. UNIX file system

The Beach Bum jfh at rpp386.Dallas.TX.US
Fri Sep 30 10:45:32 AEST 1988


In article <4136 at bsu-cs.UUCP> dhesi at bsu-cs.UUCP (Rahul Dhesi) writes:
>In article <1127 at fredonia.UUCP> mazumdar at fredonia.UUCP (Jin Mazumdar) writes:
>>Although UNIX does not have fixed length
>>records...
>
>It certainly does.  Look at the structure of /etc/utmp and /usr/adm/wtmp
>or equivalent files on your system.

not in the typical sense.  there is no file-system level support for
fixed length records.  unix files are byte streams, meaning [ with the
exception of certain device files ] you can read 1 byte or, hardware
permitting, 1MB.

with other operating systems the size of the record is fixed at file
creation time and may not be changed without copying the contents of
the file using a file conversion utility of some type.  /etc/utmp may
be read one byte at a time, except that the "records" would not have
any meaning.


-- 
John F. Haugh II (jfh at rpp386.Dallas.TX.US)                   HASA, "S" Division

      "Why waste negative entropy on comments, when you could use the same
                   entropy to create bugs instead?" -- Steve Elias



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